As the sport of water skiing has developed, so has the need for high quality, high performance water skis. Improved materials technology has practically revolutionized the water ski industry, providing new and improved water skis from recreational to highly competitive ski applications.
As the sophistication of skiers increases, there has been a significant increase in the demand for more precise and more responsive high performance slalom skis. Technological improvements have been made in numerous aspects of the water ski, including: new composite ski materials such as the most recent graphite materials, the overall outline shape and size of the ski, the shaping and contouring profile of the ski bottom, improved foot retaining supports or boots, and improved rudder and stabilizing fin configurations. Of these, the performance of a given ski configuration can be significantly altered by the rudder fin assembly.
The performance of a ski can be "customized" to the unique needs and abilities of an individual skier by making very slight adjustments in the trailing rudder fin assembly of the ski. The skier must to some extent adjust to the performance capabilities of the ski. However, since each skier has different weight, strength and athletic ability than the next, variability of the rudder fin to change the performance of the ski permits fine tuning so as to conform or customize the ski to the individual skier and the particular water conditions of the day.
Besides the development of unique designs of the fin shape and apertures therethrough, it is generally known that by moving the fin (i.e., up or down in the vertical direction and forward or backward in the longitudinal direction) relative to the ski, one can significantly alter the manner in which the ski performs on its turning edge and on its pulling edge. Such fin movement in predetermined directions enables the skier to optimize the force required to initiate turns or to angle across wakes, to improve turn stability, to regulate turn speed, to raise or lower the ski tip and the amount of ski in the water on turns and to control the ski edging. For example, moving the fin rearward on the ski slows the aggressiveness at which the ski turns on the skier's "On Side" (i.e., the skier&3 s side corresponding to his forward foot on the ski). Moving the ski down, or deeper into the water, raises the tip of the ski so that the curvature of the ski tip does not "grab" as much water, enabling the ski to complete the turn more slowly. Besides movement of the entire fin in the vertical or longitudinal directions, it is possible to selectively raise or lower only the leading or trailing edge of the fin, to address unique performance compensation requirements of the individual skier (as hereinafter described in more detail).
Since the ski will perform differently in response to each movement of the fin, ideally only one fin movement adjustment should be made at a time to minimize the effects of multiple performance characteristics. While fin movement has been possible in the prior art, heretofore known fin adjustment structures have not enabled fin adjustments to be made with any degree of precision or in a manner which permits isolation of a single fin adjustment at a time. Further, known fin adjustment techniques have no "memory" associated with the adjustment. For example, it is desirable and convenient to be able to remove the fin from the ski while traveling, to prevent damage thereto. Yet, with known fin adjustment techniques such removal of the fin results in loss of the last fin adjustment position, since it is virtually impossible to reinsert the fin back into the ski in the exact position from which it was removed, with any degree of certainty. The present invention addresses the above needs of the water ski industry by providing both a precisionally adjustable fin member that can be entirely removed from the ski and reinstalled in precisely the same position it occupied prior to removal.
A further problem associated with known fin assemblies used with skis fabricated from high-technology composites has been the tendency for the fasteners for such fin assemblies to loosen and strip from the ski body. This has particularly been a problem with the recent ski configurations that have their base material configured entirely of composite materials with no aluminum or metal sheet facing materials. Obviously, the fin and its securing bracket are subjected to tremendous pressures during operative use of the ski. Since the fin assembly is located at the back end of the ski which typically tapers to a fairly narrow width, there is relatively little ski based material available for accommodating the fin assembly anchor screws or bolts, which are generally fairly small in cross-section. As a result, the pressure and vibration transmitted through the fin assembly rapidly causes the screw or bolt fasteners holding them in place to loosen within the composite base material and oftentimes entirely strip from the ski body, rendering the ski inoperative and making repair and replacement costly and difficult. The typical method of repairing a stripped fin assembly anchor bolt hole has been to bore out the stripped hole, to fill the bore with an epoxy and metal compound, to allow the compound to harden, and to rethread the anchor screw or bolt into the hardened material. While such replacement material lasts for a while, it generally tends to strip in the same manner as the original composite ski material, requiring the process to be repeated.
The fin assembly of the present invention provides a reliable and durable mounting configuration for the fin assembly which is not susceptible to stripping during normal operative use of the ski and which provides for accurate placement and alignment of the fin assembly relative to the ski during the manufacturing process--an advantage that is generally not possible with known ski fabrication techniques.